Abstract:Aim To investigate whether lipid peroxidation injury to cultured endothelial cells (ECs) induces the expression of macrophage inflammatory protein-1α(MIP-1α). Methods The cultured human umbilical vein ECs were randomly divided into the A,B and C groups,cultured in the media containing 1 μmol/L,5 μmol/L and 10 μmol/L diamide respectively and the control group cultured in the media without diamide.After exposure of ECs to diamide for 4 h,the lipopeeroxide in the ECs was determined by thiobarbiuric acid flurophotometry;toral cellular RNA was extracted from the culrured ECS by the single step method, amd the expression of MIP-1α mRNA was determined by RT-PCR;the MIP-1α protein in ECs was determined by immunocytochemistry. Results The malomdialdehyde content in ECs im group A,B and C were 2.0-fold and 8.6-fold as much as that there was significant difference between experiment group and control group (F=138.64,P<0.01), and Q test also revealed statistical difference among the experiment groups (P<0.05). RT-PCR showed that the MIP-1α mRNA expression in ECs im group A, B and C were 4-fold, 6-fold and 3.5-fold as much as that in the control group. Immunocytochemistry assay showed that MIP-1α mRNA Protein was granular brown substance which located mainly in the cytoplasm around the nuclei.Diamide induced stronger expression of MIP-1α protein in the experimental groups. Image analysis showed that the expression of MIP-1α protein in ECs was 1.9-fold B,1.4-fold in group A and 1.3-fold in group C as mush as that in the control group.The analysis of variance proved that there were significant differences between the experimental groups and the control group (F=68.60,P<0.01),and there were also significant differences among group A,B and C which were proved by Q test (P<0.05). Conclusion Lipid peroxidation injury may play an important role in recuitment of monocytes into intima in atherogenesis through inducing ECs to produce increased MIP-1α.

Abstract:Aim To observe the effects of diabetogenic (high fat high sucrose) diet on atherogenesis in New Zealand white rabbits. Methods Two groups of New Zealand white rabbits received regular rabbit chow, or high fat high sucrose diet for 24 weeks. The levels of plasma total cholesterol, HDL cholesterol, triglycerides, insulin, and glucose were investigated, the areas of fatty streak of the aortae were measured after staining with Sodan IV, and the aortic, coronary specimens were observed with light and electron microscopies. Results The plasma glucose, and triglycerides, were significantly increased by high fat high sucrose feeding (glucose: 6.36±0.92 mmol/L vs 1.76±0.28 mmol/L, treated vs control,P<0.01; triglycerides: 1.75±0.56 vs 0.41±0.05 mmol/L, treated vs control,P<0.0001). At the end of 24 weeks, the early characteristics of atherosclerosis were present in the animals' vascular specimens (lesion areas were 8.58%±1.35% vs 0.08%±0.06%,treated vs control,P<0.001). Conclusion High fat high sucrose feeding can induce hyperglycemia, hypertriglyceridemia and atherosclerosis in New Zealand White rabbits, and this could be a potential animal model for studying the mechanisms of diabetes-accelerated a1therosclerosis. This study raised a question:What is the mechanism by which high fat high sucrose feeding induced atherosclerosis?The related hypothesis was given in this article.

Abstract:Aim To testify the inhibitory effects of transforming growth factor ( conjugated with cytotoxin saporin on proliferating vascular smooth muscle cells. Methods Conjugation of saporin to TGFα was accomplished after derivatization of saporin and TGFα with N succinimidyl 3 (2 pyridyldithio) proprionate and final purification of the conjugate was achieved within Eppendorf Centrifugal Filter Tubes. Biological assay of cytotoxicity was measured by MTS (a colorimetric method). The studies of influence of TGFα-Saporin on values of Thymidine incorporation into SMCs were measured by 3 H thymidine uptake and receptor competition studies of TGFα-Saporin are measured by adding excess TGFα in SMCs exposed for TGFα-Saporin. Results Biological assay of cytotoxicity assays testified TGFα-Saporin conjugate could inhibit specially proliferation of SMCs in culture. The absorbances measured by MTS of the group treated by TGFα-Saporin(10 7 mol/L)reduced to 60% comparedwith the control group(P=0.0003). However, the absorbances of the group treated by saporin (10 3 mol/L) only reduced to 40% of the control group. The values of thymidine of TGFα-Saporin group (10 9 mol/L) in comparison significantly decreased to 60.9% of the control group (P<0.05), suggesting that cellular DNA synthesis obviously decreased as TGFα-Saporin was added. Saporin did not affect cellular DNA synthesis at 10 3 mol/L. But excess TGFα(10 7 mol/L) added in SMCs exposed for TGFα-Saporin (10 9 mol/L) can completely blocked the inhibitory effects of TGFα-Saporin so that 3 H thymidine uptake in the group was similar compared with the blank control group. Conclusions TGFα-Saporin possesses the more effective cytotoxicit.

Abstract:Aim To investigate the role of angiotensin Ⅱ receptor antagonist losartan on the protein and mRNA expression of monnocyte chemoattractant protein 1 (MCP 1) in cultured rabbit aortic smooth muscle cells (SMC). Methods The levels of protein and mRNA expression of MCP 1 in cultured SMC and the contents of MCP 1 in the cultured media of SMC were detected by cytochemistry,situ hybridization and enzyme linked immunosorbent assay. Results 10 -6 ～10 -10 mol/L angiotensin Ⅱ(ATⅡ) increased the levels of protein and mRNA expression of MCP 1 in the cultured rabbit aortic SMC in a dose dependent manner and the co)ntents of MCP 1 in the cultured media of of SMC (P<0.001). Losartan markedly reduced the protein and mRNA expression of MCP 1 in the cultured rabbit aortic SMC and the contents of MCP 1 in the cultured media of of SMC induced by ATⅡ. Conclusions Losartan may antagonist ATⅡ induced protein and mRNA expression and secretion of MCP 1 in the cultured rabbit aortic SMC,which might play an important role in preventing the early atherosclerosis and the restenosis after angioplasty.

Abstract:Aim To observe the changes of thromboxane B₂ (TXB₂), 6-ket-Prostaglandin F1α (PGF), antithrombin Ⅲ, plasminogen in experimental carotid atherosclerosis model using air-drying in the cholesterol-fed rabbits. Methods 54 male Japanese White rabbits were randomly divided into 3 groups. The first group was fed by normal diet as empty control (n=6), the second group was fed by high-cholesterol diet as cholesterol-fed control groups (n=24),the third group was fed by high-cholesterol diet and treated by air-drying as experimental group (n=24). Animals were sacrificed at various times (from 3 days to 4 weeks) after surgery in the experimental groups and at the corresponding times in the control groups. The level of the blood lipid, thromboxane B₂, PGF, antithrombin Ⅲ and plasminogen were detected. Results The typical carotid atherosclerosis was observed in the experimental groups. The activity of antithrombin Ⅲ decreased significantly (P<0.001) and the activity of plasminogen increased significantly (P<0.001) at 4 week after air-dying in the third group. Thromboxane B₂ and thromboxane B₂/prostaglandin F in cholesterol-fed and experimental groups significantly increased compared with the empty control group (P<0.05). Conclusions The typical carotid atherosclerosis lesion can induced by air-drying in the cholesterol-fed rabbit. the pathology changes and its mechanisms were correlated with the thromboxane B₂, prostaglandin F, antithrombin Ⅲ and plasminogen changes after intimal injury.

Abstract:Aim To investigate whether antioxidants probucol, vitamin E and vitamin C modulate expression of endothelial cell adhesion molecules through regulating NF-κB activation. Methods The adhesion of HL60 cell on endothelial cells was measured with adhesion assay in a flow chamber. The effects of the antioxidative substances probucol, vitamin E and vitamin C on the expression of endothelial cell adhesion molecules were measured with cell-ELISA. The activation of NF-κB in endothelial cells was investigated in a gel shift assay. Results In TNFα-activated HUVEC, an increase in p65 and p50, a significantly increased expression of E-selectin (3.5 times), and a significantly increased HL60 cell adhesion to HUVECs (4～26 times) were detected. PDTC inhibited these increases. The half-maximal inhibition of PDTC on E-selectin expression and adhesion of HL60 to HUVEC induced by TNFα was at 18 μmol/L and 52 μmol/L, respectively. Probucol, vitamin E and vitamin C showed no effect on TNFα-induced E-selectin expression in endothelialcells, no influence on HL60-endothelial cell adhesion as well as the TNFα-induced activation of NF-κB in endothelial cells. Conclusions These antioxidants could not inhibit adhesion molecule expression.

Abstract:Aim The aims was to investigate the effects of Fluvastatin on intimal thickening and the relationship between vascular smooth muscle cells(VSMCs) proliferation, apoptosis and intimal thickening. Methods 56 Rabbits were randomized into two groups: treatment group,non-treatment group. The atherosclerotic lesions were established with high cholesterol diets and iliac artery endothelial denudation. The animals were killed and iliac arteries were removed at 1,2,4,8 w respectively. With HE staining, immunohistochemical staining and in situ cell death detection,we observed the effects of fluvastatin on the thickness of intima and intima/media, and the proliferation of VSMCs and cell apoptosis in neointima and media. Results The thickness of neointima and I/M were thinner in treatment group than in non-treatment group. Percentages of PCNA-postive cells and the content of actin in the intima of treatment group was lower than that of non-treatment group. Percentages of apoptosis in treatment group increased with the time and was higher than that of non-treatment group (P<0.05). Conclusion Fluvastatin inhibit excessive thickening of vascular intima effectively,which may partly be related to its inhibiting the proliferation of VSMCs and promoting the apoptosis of cells.

Abstract:Aim To study the expression of synaptophysin (p38) after middle artery occlusion/reperfusion in rats and the influence of nerve growth factor(NGF) on p38. Methods 72 adult female rats were divided randomly into 4 groups: false-operated group, natural recovering group, ACSF group, NGF group. The rats received left middle cerebral artery occlusion of 2 h. The sections of the brains which were subjected 6 h and 1,3,7,14,21 days of reperfusion, and were processed by immunohistochemistry with antibody against p38. Results p38 immunoreactivity was increased at 3rd day, reached its peak at 7th day, and returned almost to the controlled level at 21th day. The expression of p38 were not increased after NGF treatment. Conclusions It is suggested that there might be neuroplasticity of regeneration and repairment in central nervous system after stroke. The regulative effect of exogenous NGF on p38 need be further studied.

Abstract:Aim To determine whether coronary heart disease is associated with infection with Helicobacter pylori(HP). Methods Epidemiological and clinical studies published in full in English before October 2000 that reported on correlations between infection with HP and coronary heart disease were identified by searching Medline and medical journals. Results 20 reports available for analysis were collected. the relation between coronary heart disease and infection with HP were analysised by means of Fixed effect model of Meta-analysis. The involved total of subjects were 9737, and 4283 were patients. Mean age of the subjects in 18 studies was under 65 years. Of them the pooled odds ratio(OR) of 12 case-control studies was 1.96. OR 95 % CI was 1.76～2.18. The pooled OR of 6 cohort studies was 1.21 (95% CI, 1.07 ～1.35). Two studies that mean age of their subjects was over 70 years showed that coronary heart disease was not associated with Infection with HP. 4 studies on association between coronary heart disease and infection with CagA positive stains of HP were collected. Meta analysis showed that coronary heart disease was associated with infection, with a pooled OR of 1.52 (95%CI, 1.26～1.84). Conclusions Infection with HP was associated with coronary heart disease. Very large randomised trials would be needed to determine whether association is causal.

Abstract:Aim To explore the relationship between the pathogenesis of coronary heart disease and the rearrangement in the mitochondrial DNA(mtDNA). Methods and Results Traced mtDNA was adsorbed by glass milk method and was taken as the templet DNA of PCR directly. The nest PCR was used to test 100 bp corresponding to deleted mitochondrial DNA and was detected in five patients with coronary heart disease. A short fragment of approximately 600 bp correspondeding inserted mitochondrial DNA was detected in one patient with coronary heart disease. These didn't appear in the normals. Another short fragment of approximately 450 bp corresponded to human nucleic genome. Conclusion The mitochondrial CO2 gene may be linked to the pathogenesis of coronary heart disease. The length mutations of the mtDNA that encodes several subunits of the respiratory chain complexes contribute to the depravation of some forms of atherosclerosis.

Abstract:Aim To observe endothelium-dependent relaxing function of the patients with hyperlipidemia and coronary heart disease (CHD) and explore their clinical significance. Methods 20 cases with hyperlipidemia, thirty cases with CHD confirmed by coronary angiography were classified as two groups, CHD group Ⅰ with 17 cases, and CHD group Ⅱ with 13 cases. 20 healthy individuals are as control group. Brachial endothelium-dependent relaxing function was detected with high-resolusion ultrasound. Results Basic diameters of brachial arteries in four groups had no differences. Flow- mediated dilatations of brachial arteries in the group of hyperlipidemia, CHD group Ⅰ, CHD group Ⅱ were significantly reduced compared with control group (P<0.05,P<0.01,P<0.01). CHD group Ⅰ, CHD group Ⅱ were significantly droped compared with the hyperlipidemia (P<0.05,P<0.01). There was also significant difference between CHD Ⅰ and Ⅱ groups (P<0.01). After being sucked nitroglycerin the diameters of brachial arteries in four groups were all variously dilated. But CHD groups were signifficontly reduced compared with control group and group of hyperlipidemia(P<0.01,P<0.01). There was no significant change between CHD Ⅰ and CHD Ⅱ. There was no significant change between control group and group of hyperlipidemia. Conclusions Endothelium-dependent relaxing function was gradually reduced with the severity of atherosclerosis. It was confirmed that there is a relation between endothelium- dependent relaxing function by high -resolusion ultrasound and severity of atherosclerosis in coronary arteries and peripheral arteries.

Abstract:Aim To investigate the relationship between plasma Hcy level and conventional risk factors of CHD in MI patients. Methods 104 cases with myocardial infaction (MI) and 104 controls were recruited to participate the study. Plasma total Hcy were measured while subjects were fasting using fluorescence polarization immunoassays (FPIA). Conventional risk factors of CHD such as sex, familial history, smoking, blood pressure,blood glucose,serum choleserol,serum triglycerides,age,uric acid,creatinine and quetelet index were also measured. Results The mean plasma Hcy level was 25.17±9.31 μmol/L for MI patients, 18.41±8. 03 μmol/L for controls. Statistically, the mean plasma Hcy levels of MI patients were significantly higher than that of the controls(P<0.01). By multivariate non-conditional Logistic regression analysis,the final model consists of smoking(Or=1.066), hypertension(Or=1.128),hypercholesterolemia(Or=6.511)and Hcy(Or=2.875),which have significant relation with MI. Conclusion Hcy has strong relation with MI. Its OR was second compared with other conventional risk factors in MI patients by Logistic regression analysis.

Abstract:Aim To access the relationship between carotid lesions and some vasoactivators in patients with hypertension. Methods 105 hypertensive patients were divided into four groups based on the result of carotid arterial sonography: normal group(30 cases), endothelial thickness group(30 cases), hard plaque group(30 cases) and soft plaque group(15 cases). Several vasoactivators were determined in these patients, including nitrogen monoxide(NO), endothelin(ET), neuropeptide Y(NPY), fibrinogen(FIB), low density lipoprotein(LDL) and total cholesterol(TC). Results Compared with non-plaque group,soft plaque group had higher levels of LDLC,NPY, FIB and lower levels of NO. The difference was significant(P<0.05). Hard plaque group had also different levels of above vasoactivor parameters from that of normal group (P<0.05). Conclusion There was a significant association between the formation of carotid atherosclerotic lesions and the hypertensive injury and disorders of lipids metabolism.

Abstract:Aim To determine the relationship between ambulatory pulse pressure and carotid arteries atherosclerosis in essential hypertension. Methods 172 patients with hypertension were divided into two groups, group A: 24 h mean pulse pressure range from 40 to 55 mmHg. group B: 24 h mean pulse pressure over 55 mmHg. Carotid ultra sonography were also performed to measure intima-media thickness, lumen diameter and plaque. Maximal intima-media thickness(IMTmax) were determined as the index of carotid atherosclerosis severity. Results At the same level of mean arterial pressure (MAP), patients in group B had greater IMTmax and Lumen diameter and higher incidence of plaque than those in group A(P<0.001). Correlation analysis showed that mean pulse pressure, age, mean systolic blood pressure, years of hypertension were post correlated significantly with the IMTmax (r=0.540, r=0.470, r=0.443, r=0.231, allP<0.001), Whereas mean diasystolic blood pressure were negatively correlated with IMTmax (r=-0.28,P<0.05). Multivariate analysis showed that night pulse pressure and age were associated independently with IMTmax. Conclusion Our date showed that ambulatory pulse pressure was the most important Bp parameter during the development of carotid atherosclerosis in hypertension, and it canalso work as a effective index of evaluation severity degree of carotid atheroselerosis.

Abstract:Aim To investigate the association of C reactive protein (CRP) with carotid intima media thickness and some risk factors of cardiovascular disease. Methods Carotid IMT was measured by high resolution B mode ultrasound, and blood levels of CRP, lipids, clotting factors and fibrinolytic parameters were determined by relevant biochemical assay in 91 subjects. Results The difference in level of CRP between subjects with carotid IMT≥0.8 mm and those with IMT <0.8 mm was not significant (4.4±4.3 mg/L vs 2.7±1.3 mg/L, P=0.07), while the IMT was significantly higher in 6 subjects with CRP≥8.0 mg/L than those with CRP<8.0 mg/L (1.033±0.294 mm vs 0.812±0.222 mm,P<0.05). The level of CRP was positively correlated with triglyceride level, activities of coagulating factor VII and plasminogen activator inhibitor type 1 on multiple stepwise regression analysis. Conclusion Higher level of CRP, the reactant of inflammation, may account for the role of inflammation in the pathogenesis of atherosclerosis.

Abstract:Aim To study the changes of sex hormones, endothelial function and fibrinolytic activity in elderly hypertensive patients. Methods We selected 66 (women 34, men 32) stage Ⅰ-Ⅱ elderly hypertensive patients and 32 (women 16, men 16) elderly healthy individualsas subjects. Then their serum concentration of estradiol (E 2), testosterone (T) were measured with radio-immunoassay, plasma concentration of von Willebrand factor (vWF) were determined by enzyme-linked immunosorben assay, and tissue plasminogen activator (t PA) activity, plasminogen activator inhibitor (PAI) activity were examined by photometric techniche with chromogenic substrate. Results Elderly women with hypertension had significantly lower E 2, t PA activity and significantly higher vWF and PAI activity when compared with elderly healthy women. Elderly hypertensive men had significantly lower T, t PA activity and significantly higher vWF and PAI activity when compared with elderly healthy men. E₂ correlated negatively with vWF in elderly hypertensive women. Conclusion This study suggested that E 2 level was significantly decreased in elderly hypertensive women, and T level was significantly decreased in elderly hypertensive men. They both had significantly endothelial dysfunction and impaired fibrinolysis. Extradiol may exert a beneficial effect on vascular endothelium, then protect elderly women against hypertention.

Abstract:Aim To investigate the changes of lipid and the insulin resistance non diabetes first degree relatives of 2 type diabetes mullitus families. Methods The fasting insulin (FINS), total cholesteral (TC), triglyceride (TG) and high density lipoprotein (HDL) were measured in diabetes mullitus (DM) group, impaired glucose tolerance (IGT) group and non diabetes first degree relatives (FDR) group of 2 type diabetes mellitus families. Their spouses were selected as control group. The oral glucose tolerance test (OGTT) were conducted in all grops. The insulin resistance were assessed by insulin sensitive index (ISI)=1/FPG (fasting plasme glucose) × FINS. Results TG in DM group, IGT group and FDR group was markedly elevated (P<0.01 andP<0.05). HDL level and ISI in DM group, IGT group and FDR group were lower (P<0.05 andP<0.01). Conclusion Insulin resistance and lipid abnormalities appear early (before the development of IGT and DM) in first degree relatives of 2 type DM.

Abstract:Aim To establish a new animal model which is more suitable for the study on carotid atherosclerosis and to investigate its mechanisms. Methods 54 male Japanese White rabbits were randomly divided into 3 groups. The first group was fed by normal diet as blank control (n=6), the second group was fed by high cholesterol diet as cholesterol fed control groups (n=24), the third group was fed by high cholesterol diet and treated by air drying as experimental groups (n=24). Animals were sacrificed at various times (from 3 days to 4 weeks) after surgery in the experimental groups and at the corresponding times in the control groups. The carotid arteries were prepared for examination by light microsocopy and by transmission electron microsocopy. The intimal thickening were evaluated by intimal area/medial area ratio(I/M ratio). Results The typical carotid atherosclerosis was observed in the experimental groups. The changes included endothelial regeneration, the proliferation of smooth muscle cells and monocytes, significant intimal thickening and secondary vascularization in intimal, the formation of connective tissue matrix comprising elastic and collagen, the accumulation of lipid and cholesterol in the associated cells and in the surrounding matrix. The neointimal thickening was significant at 2 week and 4 week in the experimental groups and the I/M ratio reached 0.47±0.07 and 0.94±0.07. Conclusions The typical carotid atherosclerosis lesion can induced by cholesterol diet plus air drying in rabbit. The pathological changes and its mechanisms were more suitable for the advanced research in experimental carotid atherosclerosis.